I loved it! So much personality packed into this little fic! I absolutely believe the slumlord would have this suspicion when Superman flies onto the scene and he thought back to the way that Clark had transformed the apartment in such a quick amount of time. I also believed your reasoning as to why he'd keep his mouth shut...sure, Superman seems like a nice guy, but what's he really like when he's mad?!
At least he can bide his time, waiting for the secret to come out, then make a killing on "Superman lived here!" deals later.
So happy the challenge inspired another story! Funny to think that, as much as Clark believes his secret is safe, there are several people around the city who actually know, but are keeping quiet for one reason or another.
Now, come on readers, surely you can put something together, too! I want more stories!
